Abstract

The nonlinear decay instability of Bernstein modes pumped by an electromagnetic wave and the subsequent heating of the plasma electrons have been investigated by means of computer experiments. It was found that four pairs of Bernstein modes became unstable, and grew to large amplitudes. Each pair together with the electromagnetic wave satisfied the criteria for wave‐wave interaction. The Bernstein modes would finally saturate. The kinetic energy of the plasma electrons would then begin to increase and, over the time the code was allowed to run, the electrons would have their energy increased by a factor of 4. Saturation occurred when the Coulomb force on a particle due to the electric field of the Bernstein mode became of the order of magnitude of the Lorentz force on that particle due to the magnetic field. The electron probably had its orbital motion destroyed and became trapped briefly in the potential wells of the Bernstein mode.